Newbie help needed for a procmail script on a virt user using postfix on Debian4 reci

I followed the Virtual Users on Debian 4 recipe and now that I have it mostly working the way I want, I want to sort my incoming emails into folders. I have an account that I use for mailing lists and I receive several on this 1 address. I have folders setup already and would like to know how to get procmail to move the new messages into folders based upon criteria. Here's my maildir schema:
/var/spool/maildirs/mydomain.com/user/
In this folder I have my organized folders:
.mailing-list-1
.mailing-list-2
.mailing-list-3
and so on. I've never really used procmail before, so how would I go about getting procmail to move the messages from new/ to the correct folders? I am using maildir format.
Thanks!